Simple AJAX w/Prototype.js

From the site:

Prototype is a JavaScript Framework that aims to ease development of dynamic web applications.

Featuring a unique, easy-to-use toolkit for class-driven development and the nicest Ajax library around, Prototype is quickly becoming the codebase of choice for web application developers everywhere.

The 1.6 version of Prototype is compatible with the following browsers:

Browser Version(s)
Mozilla Firefox ≥ 1.5
Microsoft Internet Explorer ≥ 6.0
Apple Safari ≥ 2.0
Opera ≥ 9.25

With prototype, you can easily access and modify DOM elements using "utility method" shortcuts like $('element_id') or $F('element_id') to access form element values.

Using standard JavaScript to modify a DIV's text with a form's textarea value might be accomplished like this:
var textDiv = document.getElementById('textDiv');
var textInput = document.getElementById('textInput');

textDiv.innerHTML = textInput.value;
Using prototype, the same can be accomplished with the following:
$('textDiv').innerHTML = $F('textInput');
Prototype also extends JavaScript's array handling in ways that make it much easier to accomplish more complicated programming tasks.

Hopefully in future tutorials I'll be able to go deeper into some of the more amazing aspects of prototype... but today we're talking about Ajax. So let's get started!